Ok, I think I know what might be causing this (and why i cannot reproduce it) - the license is generated on a server whose time is about 2 hours off. So you might have to wait 2 hours before applying the license.

I'll try to fix this ASAP, but hopefully this will help some.

PetrServiio developer / site adminDo not send me PM for support as the solution can't be shared with others.